Geography Department

International migrations are well known to have always represented a human geographical and social phenomenon which is difficult to quantify and implicitly to analyse. The main cause of this situation is the fact that this type of migrations generally lies at the border of lawfulness (and quite often beyond it) -maybe especially within the European Union. Once the historical European borders were de jure and de facto abolished and the Schengen Area created (by signing on the 2nd of October, 1997 the Amsterdam Treaty, which entered into force on the 1st of May, 1999) our continent and its adherent power structures accepted, on their own initiative, a new challenge: that of managing large human masses endowed with a stronger and stronger ethnic and cultural diversity. In this way, during the last two decades, the mixture of European population of different nationalities (perfectly known and having a historical character) has got superposed by a significant flow of population coming from outside the continent. Although this does not represent a surprise and although certain European countries have a vast social and political experience in this field (the example of France is relevant and sufficient) it is a certainty that the phenomenon of migrations in present Europe is more and more difficult to quantify. The economic and living standard discrepancies in the contemporary world are able to break all legislative barriers; despite the numerous political efforts and xenophobe manifestations that punctually appear within the European area, in spite of the vigorous power escalation of the right wing parties, the attraction exercised by the rich and longed for (but so exigent) Europe on large masses of people can hardly be prevented. Consequently, the only realistic solution is to as exactly as possible manage the phenomenon under discussion and to as thorough as possible get to know it. The scientific deciphering of present-day

International migrations are well known to have always represented a human geographical and social phenomenon which is difficult to quantify and implicitly to analyse. The main cause of this situation is the fact that this type of migrations generally lies at the border of lawfulness (and quite often beyond it) -maybe especially within the European Union. Once the historical European borders were de jure and de facto abolished and the Schengen Area created (by signing on the 2nd of October, 1997 the Amsterdam Treaty, which entered into force on the 1st of May, 1999) our continent and its adherent power structures accepted, on their own initiative, a new challenge: that of managing large human masses endowed with a stronger and stronger ethnic and cultural diversity. In this way, during the last two decades, the mixture of European population of different nationalities (perfectly known and having a historical character) has got superposed by a significant flow of population coming from outside the continent. Although this does not represent a surprise and although certain European countries have a vast social and political experience in this field (the example of France is relevant and sufficient) it is a certainty that the phenomenon of migrations in present Europe is more and more difficult to quantify. The economic and living standard discrepancies in the contemporary world are able to break all legislative barriers; despite the numerous political efforts and xenophobe manifestations that punctually appear within the European area, in spite of the vigorous power escalation of the right wing parties, the attraction exercised by the rich and longed for (but so exigent) Europe on large masses of people can hardly be prevented. Consequently, the only realistic solution is to as exactly as possible manage the phenomenon under discussion and to as thorough as possible get to know it. The scientific deciphering of present-day

Riassunto: fattori esplicativi relativi alle differenze spaziali dell'emigrazione internazionale dalla Mmoldavia (Romania) Negli anni precedenti il 1989 la Romania era caratterizzata da una situazione politica e socio-economica particolarmente difficile. Nonostante le privazioni toccassero tutte le regioni del Paese, la parte occidentale della Romania (Transilvania e Banato), insieme alla capitale, ha sempre mostrato un tenore di vita superiore alla media nazionale, anche grazie ai contatti regolari con l'Occidente, mentre la parte orientale (Moldavia) ha sofferto storicamente di condizioni di sottosviluppo, a causa del suo relativo isolamento e della mancanza di risorse naturali strategiche. La Moldavia ha prodotto importanti flussi di emigrazione già nel secondo dopoguerra, soprattutto in direzione della Transilvania e del Banato, e delle città di Bucarest e Costanza. Il governo comunista cercò di risollevare le regioni più depresse del Paese soprattutto attraverso lo sviluppo dell'industria pesante. Questi impianti, tuttavia, non sempre si inserivano nel tessuto socio-economico locale e spesso si sono mantenuti in attività solo grazie alle sovvenzioni statali. La progressiva liberalizzazione economica avvenuta dopo il 1989 ha portato alla chiusura di molte di queste industrie. Un altro importante cambiamento per la società rumena è stata la liberalizzazione della circolazione delle persone, anch'essa successiva al 1989. La mobilità interna e l'emigrazione verso l'estero, soprattutto a partire dall'anno 2000, costituiscono uno dei fenomeni socio-economici più importanti della Romania di oggi. I dati statistici ufficiali sull'emigrazione, ricavati dal Censi-(

International migrations are well known to have always represented a human geographical and social phenomenon which is difficult to quantify and implicitly to analyse. The main cause of this situation is the fact that this type of migrations generally lies at the border of lawfulness (and quite often beyond it) -maybe especially within the European Union. Once the historical European borders were de jure and de facto abolished and the Schengen Area created (by signing on the 2nd of October, 1997 the Amsterdam Treaty, which entered into force on the 1st of May, 1999) our continent and its adherent power structures accepted, on their own initiative, a new challenge: that of managing large human masses endowed with a stronger and stronger ethnic and cultural diversity. In this way, during the last two decades, the mixture of European population of different nationalities (perfectly known and having a historical character) has got superposed by a significant flow of population coming from outside the continent. Although this does not represent a surprise and although certain European countries have a vast social and political experience in this field (the example of France is relevant and sufficient) it is a certainty that the phenomenon of migrations in present Europe is more and more difficult to quantify. The economic and living standard discrepancies in the contemporary world are able to break all legislative barriers; despite the numerous political efforts and xenophobe manifestations that punctually appear within the European area, in spite of the vigorous power escalation of the right wing parties, the attraction exercised by the rich and longed for (but so exigent) Europe on large masses of people can hardly be prevented. Consequently, the only realistic solution is to as exactly as possible manage the phenomenon under discussion and to as thorough as possible get to know it. The scientific deciphering of present-day

Indiferent de perioada istorică la care ne referim, cadrul natural a jucat un rol determinant în ceea ce priveşte geneza şi evoluţia aşezărilor omeneşti. El a dirijat întotdeauna logica primară a închegării reţelelor de aşezări, precum şi gama de activităţi economice productive, pe baza căreia s-a asigurat dezvoltarea, toate aceste relaţii fiind însă moderate şi modulate de marea varietate a condiţiilor sociale din diferite epoci.

On the basis of historical information, cartographical materials and the data mentioned, several periods may be distinguished in the evolution of the lakes from the Bahlui watershed:
- he historical period, up to the beginning of the XIX century, when the majority of the lacustrine areas appeared, both as landscape elements and complex economic sources. The majority of the lacustrine areas from this drainage basin were documentarily mentioned starting with the 15th century. Still, for a series of pounds we do not have documentary materials to attest the period in which they appeared.
- the modern period, that covers the 19th century and the first half of the 20th century is marked by two phases of regression of the number of lakes in this basin (at the beginning of the 19th and 20th century), especially of the little ponds, due to a number of certain socio-economical factors, agricultural reforms, lack of continuity in their accordingly management.
- the contemporaneous period, that starts with the second half of the 20th century, is characterized by the applications of several territorial systematisation programmes, the majority of the lakes in the Bahlui, drainage area being reconditioned and hydrotechnically improved
Nowadays, for the lacustrine units from the Bahlui drainage basin, special programs appealing to teledetection and GIS programs are used in the attempt of the conservation and monitoring of the lacustrine ecosystems, through an efficient management of the hydric and economic resources.

The drainage area of the Bahlui river lies, geomorphologically speaking, in the south of the Moldavian Field, with a little fragmented relief. The profound geological formations are made up of Sarmatian clay that alternates with thin layers of fine sands. These rocks are being covered by new Quaternary deposits such as alluvia and loessoid clays. The alluvia that makes up the Plain of Bahlui (clay, sand and gravel) appeared as a consequence of the transport and accumulation of this river.On both sides of the Valley of Bahlui there are terrace deposits made up by clay and loess in the upper part and sand with a little gravel as the basis.The geomorphological and geological conditions in this area allow the appearance of water bearing strata with a great capacity of retaining water.
With the deep geological hydrostructures, waters are stored in captive water bearing strata.These waters are under pressure and therefore have a tendency to go up.
According to the geomorphological and lithological conditions in the middle section of the Bahlui basin several superficial hidrological structures have been identified.
a) geological hydrostructures at the basis of the loess and clay deposits;
b) geological hydrostructures in the river's terraces;
c) geological hydrostructures of the Quaternary side deposits;
d) geological hydrostructures of the Quaternary plain deposits.

The study bellow is to confirm that we have tried to analyse the main aspects of
maximum amount of precipitation in 24h in the region of Bahlui hydrographic basin. This
parameter represents one of the most important characteristics of atmospheric precipitations.
We paid a special attention for spatial distribution of historical maximums values wich
indicates a direct correlation with altitude (167mm at Barnova in the south hilly area instead of
70mm at Harlau at the lee side of Dealu Mare hills). This distribution is in a direct relation with
the number of days with precipitation overpassing 20mm and 30mm. Some aspects of this
parameter are peculiar facts of continental climate, wich is specific for this region, as the
intensification of rainfall during the summer when almost 60% of maximum amount of
precipitations in 24 h are concentrated. Meanwhile, in the summer, the frequency of maximum
amount of precipitation in 24h overpassing 30 mm exceeds 20%. Also, the part of annual
maximum amount in 24h in the annual amount of precipitation – 10% in average, reaching
even 20% in somes years - sustain the same arguments of continentality.

Condiţiile geologice, geomorfologice, climatice, hidrologice şi hidrogeologice
constituie premise esenţiale în generarea unor caracteristici hidrochimice deosebite ale apelor
subterane în partea de est a României, caracteristici uşor modificate datorită unei umanizări
intense. Valea râului Prut constituie un culoar de convergenţă a acestor caracteristici, iar apele
freatice cantonate în şesul aluvial reflectă aceste influenţe. Datele analizate demonstrează că
aceste ape se încadrează în categoriile de potabilitate (limitele admise) numai în ceea ce
priveşte reacţia, conţinutul de substanţe organice şi de elemente chimice de tipul Fe şi Mn. Însă
limitele maxime admise sunt cu mult depăşite în ceea ce priveste duritatea, reziduul fix,
conţinutul în diferite elemente chimice (Ca, Mg, NH4, NO3, NO2, SO4), astfel încât se poate
considera că, din punct de vedere al calităţii apelor freatice, valea Prutului nu dispune, cel putin
pentru sectorul romanesc, de resurse de apă freatică, care să poată fi valorificate economic, cu
excepţia poate a sectorului Rădăuţi-Prut-Ripiceni, care se încadrează pentru mai mulţi
parametri în limitele normale, dar nu în totalitate.

Resursele de apă dintr-un bazin hidrografic pot fi apreciate în modul cel mai sintetic pe baza analizei caracteristicilor scurgerii medii într-o perioadă lungă de timp (de cel putin 20 de ani). Acest tip de analiză urmăreşte în primul rând evaluarea debitului lichid, a debitului mediu specific, a stratului de apă scurs, a volumului de apă transportat, a diferiţilor coeficienţi legaţi de scurgerea medie (coeficientul modul, coeficientul de variaţie etc.).
În vederea analizei scurgerii medii pentru bazinul hidrografic Bahlui au fost examinate and prelucrate şirurile de debite medii lunare and anuale determinate pentru perioada 1950-2004 la 9 staţii hidrometrice existente în cuprinsul bazinului, cu durate directe de funcţionare cuprinse între 28 and 54 de ani. Rezultatele obţinute ne-au permis să încadrăm acest bazin în tipul de regim hidrologic PVIT (primăvară-vară-iarnă-toamnă, după Ujvari, 1972) cu umiditate deficitară, scurgerea medie anuală neacoperind decât într-o măsură foarte mică necesarul de apă al populaţiei din această parte a ţării.